Spring Boot JPA-没有合格的bean类型

Question

I'm learning Spring and things were going well but suddenly running into this issue where it cannot find a qualified bean. Hitting the wall, even in a new app I'm getting this.

Let me know if you need more, going to take a break! I must be missing something very simple.

Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException:
  No qualifying bean of type [com.alco.repository.ContactRepository]
  found for dependency [com.alco.repository.ContactRepository]:
  expected at least 1 bean which qualifies as autowire candidate for this dependency.
  Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}

My dependencies:

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-rest</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-hateoas</artifactId>
    </dependency>
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-security</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

    <dependency>
        <groupId>com.h2database</groupId>
        <artifactId>h2</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

Contact class:

package com.example.entity;

import java.io.Serializable;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;

@Entity
@AllArgsConstructor
@NoArgsConstructor
@Getter
@Setter
public class Contact implements Serializable {

private static final long serialVersionUID = -1340978779095092824L;

@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private String id;
private String firstName;
private String lastName;
private String address;
private String phoneNumber;
private String email;

}

The simple interface:

package com.alco.repository;

import org.springframework.data.jpa.repository.JpaRepository;

import com.alco.entity.Contact;

public interface ContactRepository extends JpaRepository<Contact, String> {

}

Answer 1

I think you're missing enabling of the JPA repositories:

@ComponentScan(basePackageClasses = ...)
@EntityScan(basePackageClasses = ...)
@EnableAutoConfiguration
@EnableJpaRepositories(basePackageClasses = ...)
public class ... {
}

This would be for your configuration class.

Answer 2

The only thing I can see is this; please try with changing JpaRepository with Repository

import org.springframework.data.repository.Repository

public interface ContactRepository extends Repository<Contact, String> {

Answer 3

You need to annotate your repository with @Repository , otherwise Spring will not manage your Repository class.

Do not use the more generic @Component , as it may lead to different behavior, eg in Exception Management. As an example, look at this parte of the Spring Documentation .

Excerpt:

The postprocessor automatically looks for all exception translators (implementations of the PersistenceExceptionTranslator interface) and advises all beans marked with the @Repository annotation so that the discovered translators can intercept and apply the appropriate translation on the thrown exceptions.

Also, as mentioned here , in the future you might have back-compatibility issues.

As an alternative, you can use @EnableJpaRepositories and specify where Spring should be looking for repositories.